In some countries, pet owners are obligated by law to remove waste material produced by their pet on a public property. Even where no law to that effect exists, pet owners are usually expected to remove such waste material, as waste material left on the streets, sidewalks, etc. is generally unappealing and unhygienic.
A number of scooper devices, i.e. devices used to pick up waste material on the ground, have pincer-like arms which are inserted in a bag and used to pick up the waste. The bag is then inverted, placing the soiled surface and the waste material inside the bag. However, pincer-like scoopers are generally not adapted to be used as catchers, i.e. to catch waste before the waste contacts the ground. Scooped waste material generally leaves a waste residue on the ground, which can be a health hazard, especially for children.
A variety of devices allow for support of a bag in an open position, the bag being maintained under the animal before the waste is produced, thus catching the waste in the bag which is then removed from the device and thrown away. The problem with such devices is that the bag can become soiled, either by the falling waste itself if the open end of the bag is not adequately aligned under the animal, or by the ground where the bottom of the bag makes contact. Thus, the user can be required to manipulate a dirty bag, which is not desirable. 
Accordingly, improvements are desirable.